Motion transfer device



Dec. 5, 1967 D. w. BARTON ETAL 3,355,963

MOTION TRANSFER DEVICE Filed Dec. 9, 1965 DAV/D "(BARTON CHARLES HADDAD INVENTORS 9.4. I2. ea-1M BY q/wxww ATTORNEYS United States Patent 3,355,963 MOTION TRANSFER DEVICE David W. Barton, Birmingham, and Charles Haddad, Allen Park, Mich., assignors to Ford Motor Company, Dearborn, Mich., a corporation of Delaware Filed Dec. 9, 1965, Ser. No. 512,749 Claims. (Cl. 74--501) The present invention relates generally to motion transfer devices.

In control systems for various mechanisms including automotive heaters, it is sometimes necessary to convert rotary motion to linear motion. The present invention relates to a simple but effective means for connecting a rotary control to a linear actuator.

The many objects and advantages of the present invention will become apparent from the following discussion when considered in connection with the accompanying drawing, in which:

FIGURE 1 is a perspective view of a control mechanism for an automobile heater incorporating the present invention;

FIGURE 2 is a perspective view of a prior art device;

FIGURE 3 is a perspective view of a portion of the control mechanism employed in FIGURE 1; and

FIGURE 4 is a modification of the structure disclosed in FIGURE 3.

The concept of the present invention has a variety of applications. For illustrative purposes, it will be described in connection With the heater control mechanism illustrated in FIGURE 1.

Heater control assembly is constructed to perform three control functions; the first of these is to control the operation of the heater blower motor; the second function is to control the door or valve in the inlet to the heater; and the third function is to control the temperature of the outlet air by controlling the amount of air flow through the core of the heater.

The control assembly 10 includes a molded plastic housing 12 that includes a flange 14 at one end. The flange 14 is of generally arcuate shape and has an elongated slot 16. A shaft 18 extends through the slot 16 and has a knob 20 connected to its protruding outer end. An electrical switch 22 of the sequentially operated push type is secured to an upstanding housing portion 23 at the rearward end of the housing 12. The shaft 18 extends through housing portion 23 and has its rearward end connected to the switching element of the switch 22.

Electrical wires 24 are provided to connect the switch 22 in circuit with the power source and the heater blower motor.

The control knob 20 may be pushed inwardly to operate the switch 22. Switch 22, being of the sequential-1y operated type, is actuated by pushing a centrally situated switching element. Assuming the switch 22 is in the off position when the button 20 is pushed, the switch turns the blower motor to a low speed. When the control knob 20 is pushed a second time, the switch turns the blower motor to high speed and when the control knob 20 is pushed a third time the blower motor is returned to an off position.

A connecting member 26 is slidably mounted on the shaft 18. A coil spring 28 is situated about the shaft 26 and presses the connector element 26 against the backside of the arcuate front flange 14. A Bowden wire assembly 30 has its outer casing 31 secured to the housing 12 by a clamp 32. The control wire 34 situated within the Bowden wire 30 has its exposed end secured to the connecting member 26. When the control is moved to a right-hand location, heated air is directed to the defroster outlets.

A pinion gear 36 is mounted upon shaft 18 and is rotatable therewith. The gear 36 is positioned against the up- 3,355,963 Patented Dec. 5, 1967 standing portion 23 of the housing 12 by means of a spring 28. A Bowden wire assembly 40' has its outer casing 41 1 secured to the housing 12 by a clamp 42. A control wire 44 is situated Within the sheath 41 of the Bowden wire 40. One end of the wire 44 is connected to a heater air passage control valve and the other end 45 protrudes from the clamp 42. The end 45 of the control wire 44 is bent into the serpentine configuration illustrated in FIG- URE 3. The configuration is formed by a series of loops 46 that are connected by straight portions 48.'The straight portions 48 are spaced apart a distance P that is equal to the pitch of the pinion gear 36. The serpentine end 45 of the control wire 44 slides within guide members 50 and 52 formed in the housing 12 and is in mesh with the teeth of the pinion gear 36. With this construction, the knob 20 may be rotated in either a clockwise or counterclockwise direction and thecontrol wire 44 is thereby retracted or extended to control the amount of inlet air that flows through the heater core or bypasses it.

The construction of the motion transfer means is characterized by its simplicity. The portion 45 which engages the pinion gear 36 is integrally formed of the control wire 44. The construction is straight forward, cheap and effective. If a prior art construction were used, it would very likely be of the type illustrated in FIGURE 2. In FIGURE 2, a die cast metal rack 54 is provided with a plurality of gear teeth 56 that engage the teeth of a driving pinion. A pin 58 is secured to the die cast rack 54. The end of the control wire 60 of a Bowden wire assembly 62 is wrapped around the end of the pin 58. This construction employs two more parts: than the assembly illustrated in FIGURE 3. In addition to the cost of fabricating these additional parts, there is also the associated cost of assembling them. It is quickly apparent that the construction of FIGURE 3 is a significant step forward in the art.

An alternate embodiment of the invention is illustrated in FIGURE 4. In that view, a Bowden wire assembly has an internal wire 144 with an end portion 145 bent into the square cornered serpentine construction illustrated. In this view, the perpendicular portions 148 are spaced apart a distance equal to a whole number multiple of the pitch of the pinion 36. It may be desirable for assembling or manufacturing reasons to form the end of the wire 145 into the square cornering shape illustrated in FIGURE 4. The driving ratio between the pinion and the wire is not changed. This alternate construction is merely proposed to illustrate the versatility of the invention.

The foregoing description illustrates the presently preferred embodiment of this invention. Modifications and alterations may occur to those skilled in the art that will come within the scope and spirit of the following claims.

We claim:

1. A motion transfer device comprising:

a housing,

a rotatable input member having a gear means rotatably connected to said housing and constructed to rotate about a fixed axis,

a control wire,

said control wire having an integrall end portion formed into a serpentine configuration,

means connecting said end portion to said housing for sliding movement,

said gear means being in driving engagement with the end portion of said control wire.

2. The motion transfer device of claim 1 and including:

said gear means having a series of circumferentially spaced apart teeth forming the periphery thereof,

said means connecting said end portion to said housing restricting movement of said end portion to linear movement,

said serpentine end portion comprising a continuous series of spaced apart portions extending generally parallel to the axis of rotation of said gear means,

said parallel portions being spaced a distance equal to a whole number multiple of the pitch of said gear means.

3. The motion transfer device of claim 1 and including:

said end portion of said control wire comprising a continuous series of spaced apart connected loops,

said gear means having teeth in driving engagement with said end portion. 4. The motion transfer device of claim 1 and including: said gear means having a series of circumferentially spaced apart teeth forming the periphery thereof, a flexible hollow conduit disposed about said control wire,

said conduit having one end secured to said housing,

said end portion of said control wire extending beyond the end of said conduit,

said end portion comprising a series of portions extending generally transverse to the plane of rotation of said gear means,

said just mentioned portions being spaced apart a distance equal "to the pitch of said gear means,

the teeth of said gear means being in driving engagement with the end portion of said control Wire.

5. The motion transfer device of claim 1 and including:

said end portion 'being formed in an uniplanar curve,

said means connecting said end portion to said housing restricting movement of said end portion to the plane of said curve.

References Cited UNITED STATES PATENTS 948,155 2/1910 Baldwin 74-507 2,496,785 2/1950 Finneburgh et a1. 7450l X 2,614,437 10/1952 Meggitt 74-507 X 2,912,873 11/1959 Little 74501 X 3,021,580 2/1962 Rowitz 25477 X 90 FRED C. MATTERN, JR., Primary Examiner.

C. F. GREEN, Assistant Examiner. 

1. A MOTION TRANSFER DEVICE COMPRISING: A HOUSING, A ROTATABLE INPUT MEMBER HAVING A GEAR MEANS ROTATABLY CONNECTED TO SAID HOUSING AND CONSTRUCTED TO ROTATE ABOUT A FIXED AXIS, A CONTROL WIRE, SAID CONTROL WIRE HAVING A INTEGRAL END PORTION FORMED INTO A SERPENTINE CONFIGURATION, MEANS CONNECTING SAID END PORTION TO SAID HOUSING FOR SLIDING MOVEMENT, SAID GEAR MEANS BEING IN DRIVING ENGAGEMENT WITH THE END PORTION OF SAID CONTROL WIRE. 